Shielded connector device



June 20, 1939. Q SCHNQDER 2,163,412

SHIELDED CONNECTOR DEVICE Filed July 8, 1956 cououcnva I0 comma ON /3INNER AND OUTER SURFACES INVENTOR O SCHNEIDER BY 7k M ATTORN EY PatentedJune 20,1939

UNITED STATES PATENT OFFICE Application July 8, 193a, Serial No. 89,810

In Germany Amst 2,, 1935 2 Claims. (Cl. 173-330 In the installationoiradio lines or conductors, special care must be taken so that theywill not become subject to extraneous disturbing electrical fields. Forthis reason so-called shielded 5 leads or lines have been adopted inpractive In such shielded connections of the kind in question, moreparticularly in broadcast installations for the antenna feeder ordownlead-{it is necessary that the sliielding,-means all the way fromthepick-up conductor, that is to say, the receiving aerial to the receiverproper should not present any break. Inasmuch as the use of suchshielded lines or downleads has of late become popular also forinstallations in rooms or under similar conditions, the latter had to beadapted to the power or fighting circuits that are usually present. Theradio lead, that is to say, more particularly the antenna lead, is theninstalled most preferably in a fixed or stationary manner and is thbrought to a socket, whence connection is est blished with the receiving'set proper by way and means of a flexible cable fitted with a.v

connector plug.

Now, if such a socket and plug connector device is to preclude all risksof the line being throughout safeguarded from actions of extraneousdisturbing fields, then a. galvanic or conducting connection must beprovidedbetween the shielding means of the fixed line andthe fiexiblecable and socket connection. In otherwords, the problem arises toprovide a plug and socket connection which will assure galvanic orconducting union between the two shielding means, while in addition thelead for the radio frequency energy at this point will be protected fromdisturbing in- The present invention discloses a shielded plugconnection which establishes a. metallic junction between the shieldingmeans of the lead and the shielding means of the cable and plug, suchthat the entire line or downlead will be throughout surrounded andsafeguarded by a shield.

The plug is so designed that a bipartiteshell or casing made of metalinsures. the desired connection between the shields. The plug shellproperly so-called consists preferably of an insulation material capableof being sprayed; internally, it is provided with a metallized coatapplied by spraying methodsknown in the prior art, so as to provide ashield. This top part is closed by a metallic base plate or a platebearing a metallized layer to which the plug contact is fastened. The RFlead is in the form of a concentric or co-axial central conductor whoseshield should be connected with the case.- This connec-v tion betweenthe shield of the lead and the shell or envelope of the plugis insuredby the pressing on of the metallic base plate. Satisfactory unionbetween the shield and the socket is insured .preferably by acylindrical appendage piece which is 5- introduced into a matching bush0! the socket. 1

Locking by spring cam pieces in the socket and a suitable part in theshell contact of the plug prevent inadvertent loosening of the contactwhen the cable is touched and moved, say in dusting 10 or cleaning.

Inasmuch as such a shielded fiexible cable is very liable to-change itscapacity values when subject to fiexure, etc., the shield is made 0! acomparatively large diameter so that it is not 15 particularly suitedfor, sharp bends and flexing.

However, because of the fact that it is often necessary in practice tobring the flexible cable away-.from the socket at right angles, it'willbe seen that the standard type oi socket con- 20 struction is frequentlyunsuited. Hence, the

. present invention discloses a plug whose prong is disposed angularlyin reference to the cable that is led away so that, upon the plug beinginserted, the flexible cable may, for instance, be led 25 in downwarddirection without incidental flexing thereof, in fact, it will then besubject only to tractive efi'orts.

For a better understanding 0! the invention, reference is made to theaccompanying drawing, 30 in which;

Fig. l is a perspective view of a plug connection embodying theinvention,

Fig. 2a is a sectional view and Fig. 2b a rear view of the device ofFig. 1 and, 35 Fig. 3 is a side view of the plug as inserted in a wallsocket.

As shown, a hollow plug member I has an opening at its rear side inwhich is seated a base or mounting plate 2, these members being formed40 of any suitable insulation materials As shown the main plug member iscoated on'both its inner and outer surfaces with a metallic coating Ill.The central conductor H of the cable which is to be connected to theradio device such as are- 45 ceiver, is enclosed in a metallic shield 5,both these members entering the plug through an aperture I2 formed inone end thereof, As shown the cable I I is secured to the end of theplug connector or prong 4 as by means of the nuts I3, the 50 lower nutalso serving to secure connector 4 rigidly to the plate 2. Attachingscrews 3 pass into the main body of the plug and secure plate 2 inposition and also an overlying metallic plate l4 which has an end Iturned under the lower 55 ring 6 is provided which surrounds the prong 4but is insulated therefrom. Contact ring 6 engages the sides of anopening 16 in the socket or casing I thereby providing a conductiveconnection between the latter and shield 5. When in position, the end ofplug 4 may enter a bushing or sleeve I! by inward or outward pressureapplication to ensure satisfactory connection with the shielded antennalead l8 which may. enter the casing from the rear. The plug devicedescribed cannot be mistaken or used for a power or lighting circuitplug so that damages and injuries to the receiver are'prevented.

Having'described my invention, what I claim as novel and desire tosecure by Letters Patent is:

- 1. A connector device for connecting the conductor of -ashielded'transmission cable to electrical apparatus comprising acup-shaped casing of insulation material, means for shielding saidcasing comprising a coating of a metallic substance on at least one ofthe surfaces of the casing, a closure for said casing comprising ametallic plate mounted within the casing, a plug mounted on said platebut insulated therefrom whereby the plug is insulated from the coatingon said casing, means within said casing for receiving the shieldedcable and connecting the inner conductor thereof to the plug, 'ametallic contact cylindrical member secured to said metallic plate andsurrounding but insulated from said plug, and a conductive connectionwithin said casing between the shielding means of'the cable and thecoating of metallic substance .to' provide continuity between the cablesurrounding meansand the metallic coating. Y

2. A connector device for joining a conductor in one shielded cable to aconductor in another shielded cableand at the same time provide ashielded joint and conductive connections between the shielding means ofthe two cables and the shielding means of the joint comprising a plugconnected to the end of the first named conductor which is to be joinedto the other conductor, a cooperative plug receptacle connected to theend of said other conductor that is to be joined to the first namedconductor, a. cup-shaped casing for said plug composed of insulatingmaterial, acoating of metallic shielding material on said casing, meansfor securing said plug to said casing comprising a metallic cover memberfor the cup-shaped casing, said plug being insulated from said covermember and means supported by said cover member in cooperation with saidcupshaped casing providing a conductive connection between the shield ofthe first cable and the metallic layer on the casing, a cylindricalmember supported on said cover member and electrically connectedthereto, said cylindrical member being positioned so as to surround butnot contact said plug, said receptacle including means for contactingsaid cylindrical member when the plug is inserted in the receptacle forproviding a conductive connection between the cylindrical member and theshield of said second conductor.

OSKAR SCHNEHDER.

